Recently some American scientists have given a useful piece of advice to people in industrialized nations．They say people should eat more of the same kind of food eaten by humans living more than 10,000 years ago． {#blank#}1{#/blank#}

    The scientists say that the human life has changed greatly．Our bodies have not been able to deal with these changes in lifestyle and this had led to new kinds of sicknesses． {#blank#}2{#/blank#} So they are called “diseases of civilization”．Many cancers and diseases of the blood system are examples of such diseases.

    Scientists noted that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none． {#blank#}3{#/blank#} However, a change in food is one of the main differences between life in ancient times and that of today.

    Stone Age people hunted wild animals for their meat, which had much less fat than domestic ones．They ate a lot of fresh wild vegetables and fruits．They did not have milk or any other dairy products, and they made very little use of grains． {#blank#}4{#/blank#} We eat six times more salt than our ancestors．We eat more sugar．We eat twice as much fat but only one third as much protein and much less vitamin C.

    {#blank#}5{#/blank#} But scientists say that we would be much healthier if we eat much the same way the ancient people did, cutting the amount of fatty, salty and sweet food.

A．Stone Age people lived a simple life.

B．But today, we enjoy eating a lot of these.

C．In that case, they would live much healthier.

D．Ancient people also got lots of physical exercise.

E．These new sicknesses were not known in ancient times.

F．People today probably don't want to live like our ancestors.

G．Modern people used to suffer from “diseases of civilization”.

    Electronic sensors built into paper could be used in a range of ways from information storage to touch screens and more.

    Electronic sensors built into cartons（纸盒）may make it easier to tell when it's time to throw out rotten milk or orange juice. And that's just the start. At least that's the goal for researchers working on putting electronics into paper. They're trying to figure out how to combine the flexibility, low-cost and recyclability of paper with the information-carrying ability of electronics.

Daniel Torbjork, a physics graduate student in Finland, has been working on the problem. He's published a review of the field in the journal Advanced Materials.

    Much research has been focused in this area. While most electronic applications require patterned conducting structures, conductive paper could be used in applications such as energy storage devices, sensors, electric heaters and others, according to Torbjork.

     “You could even have some interactive functions in magazines,” Torbjork said, “You could put a simple game in a package. If you want a touch screen, press a button and then something happen. Sensors in paper could tell us when something has gone bad.”

    Additional applications, such as information storage and security paper, have been suggested for magnetic papers containing magnetite. In Massachusetts, researchers have figured out how to post a video of such a device put into a paper airplane.

    German researchers have also put electronic chips in paper bank notes to defend counter-feiters（造伪币者）. Paper is a good material but printing electronics also requires low-cost manufacturing. As many US and European paper makers lose market share to cheaper paper from China, these big paper companies are looking for added value products. That's where electronic paper devices could make a difference.

    “The major obstacles are paper's large surface roughness and chemical impurities.” Torbjork says. But others in the field think that electronic sensors in paper are still far from the consumer marketplace.

    “I don't think it's going to happen.” said Roy Horgan. “You need a conductive surface. It could be 10 years out. What we are looking for are solutions that you can commercialize to­day.”

    Solar Print is partnering with Italian automaker Fiat to develop a unique auto-glass with tiny photostatic cells（光电）that can capture electricity from the sun. In the meantime, using paper to conduct electricity is still a “blue-sky” project.

    “I would love to see someone prove me wrong, because that means that it's actually happening.” Horgan said. “If someone comes up with conductive paper, then that's a very interesting technology.”

    For centuries, in the countries of South and Southeast Asia, the elephant has been an important part of the culture, economy and religion. And nowhere more so than in Thailand. Unlike its African cousin, the Asian elephant is easily domesticated. The rare so­called white elephants have actually lent the power of royalty to its rulers, and until the 1920s the national flag was a white elephant on a red background. To the early Western visitors, the country's romantic name was "Land of the White Elephant"．

    Today, however, the story is very different. Out of work and out of land, the Thai elephant struggles for survival in a nation that no longer needs it. The elephant has found itself more or less deserted by previous owners who have moved on to a different economic world and a society in the western part. And while the elephant's problems began many years ago, now it has a very low national advantage.

    How does the national symbol turn into ignored animals? It is a story of worse environment and the changing lives of the Thais themselves. According to Richard Lair, Thailand's expert on the Asian elephant and author of the report Gone Astray, at the turn of the last century, there may well have been as many as 100,000 national elephants in the country.

    In the north of Thailand alone, it was estimated that more than 20,000 elephants were employed in transport, 1,000 of them alone on the road between the cities of Chiang Mai and Chiang Saen. This was at a time when 90 percent of Thailand was still forest—a habitat that not only supported the animals but also made them necessary to carry goods and people. Nothing ploughs through thick forest better than lots of sure­footed elephants.

    By 1950 the elephant population had dropped, but still to the number of 13,397. However, today there are probably no more than 3,800, with another 1,350 wandering free in the national parks. But now, Thailand's forest covers only 20 percent of the land. This deforestation (采伐森林) is the central point of the elephant's difficult situation, for it has effectively put the animals out of work. This century, as the road network grew, the elephant's role as a beast of burden decreased.

    Shan Tianfang, died at 83 on Sept. 11, 2018 in Beijing because of multiple organ failure. His energetic oral interpretations of classical Chinese novels and historical events pushed the ancient pingshu tradition forward into the modern age for generations of Chinese.

    Mr. Shan tried for many years to avoid becoming a performer of pingshu, the Song dynasty-era storytelling tradition. Growing up in the1950s in a family of folk art performers, he had seen struggle firsthand. It was a life of constant financial troubles and low social status. So it was with great unwillingness when, out of financial necessity, he became an apprentice(徒弟) to a family friend who was a master of pingshu. He made his first public appearance in 1956.

    In the pingshu tradition, the performer wears a traditional gown and sits behind a desk equipped with a folding fan and a wooden block. The storyteller tells a legend — typically a classical Chinese epic — from memory, using different voices and exaggerated gestures as well as adding occasional background detail and commentary.

    Mr. Shan grew to love the storytelling form, which is popular across northern China. It is a demanding profession that combines acting, oration, writing, historical research and literary criticism and requires countless hours of memorization. In teahouses around the northeastern region, he became famous for his fresh takes on the classics.

    In 1976, many Chinese were hungry for some new forms of entertainment, and it was against this background that he grasped the opportunity to record a pingshu radio broadcast. He soon discovered that performing on radio was vastly different from doing so in teahouses. There were no props(道具), no reactions from the audience to guide him — just Mr. Shan and the microphone in a recording studio. So for his first radio performance, a shortened version of the historical novel. The Romance of Sui and Tang Dynasties, Mr. Shan used the studio's three recording technicians as his audience and adjusted his performance based on their reactions.

    The performance had its first appearance in 1980 on Chinese New Year, and more than 100 million Chinese were estimated to have tuned in during the 56 hours over which it was broadcast. It was the beginning of a dramatic second act both for Mr. Shan and for pingshu in the People's Republic of China. He was soon a household name across the country.

    Over six decades, Mr. Shan recorded more than 110 stories for radio and television totaling about 12,000 episodes and lasting 6,000 hours. His best-known works include his interpretations of Chinese classics like 'White-Eyebrow Hero' and 'Sanxia Wuyi' and his dramatizations of historical figures like Zhuge Liang and Lin Zexu.

    Even today, hop into a Beijing taxi and the driver may be listening to one of Mr. Shan's recordings. "For my generation, Shan Tianfang was a master," said Zhao Fuwei, 48, a Beijing taxi driver. If back then there was such thing as a viral star, then Shan Tianfang was definitely the hottest viral star.

    "Listening to his stories has made it easier to kill time in bad traffic," Mr. Zhao added. "He was so good at making complicated historical stories simple and interesting". You feel like you could empathize with the characters in his stories, even though they lived a long time ago.

    But in recent years many of the great pingshu performers have died, and the tradition is fading. By the time Mr. Shan retired in 2007, interest in pingshu among Chinese had all but been replaced by mobile phones and gaming. Nevertheless, even after retiring, Mr. Shan worked tirelessly to promote pingshu among young Chinese, instructing apprentices and starting a school dedicated to the folk arts.

    Ever willing to adapt to new technologies, he posted a message to his Sina Weibo microblog account on Sept. 6, five days before his death. It was an announcement about a new live-streamed(直播) lecture series about pingshu.

    Babies' main food is rice cereal. But it is often poisoned. Studies have found that many brands contain measurable amounts of inorganic arsenic(无机砷),the most poisonous kind. It's not just nice: an August 2018 study tested 50 foods made for babies, including organic and nonorganic brands such as Gerber, Earths Best, and other popular labels, and found evidence of at least one dangerous heavy metal in every product. Fifteen of the 50 contained enough contaminants(污染物)to pose potential health risks to a child eating one serving or less a day.

    Heavy metals can damage cognitive(认知的)development in children, who are especially at risk because of their smaller size. Inorganic arsenic in drinking water has been found to lower the IQ scores of children by five to six ills. And as heavy metals accumulate in the body over time, they can raise the risk of cancer, diabetes and other physical conditions. Of course, finding you're your favorite brand is contaminated is not a reason to panic. Low levels of exposure for short periods are unlikely to cause serious effects, but parents should focus on reducing the overall levels of these poisonous substances in their children's total diet to limit harm.

    Heavy metals occur naturally on Earth and are present in soil and water. But pesticides(杀虫剂), mining and pollution increase their concentrations, and farming and food manufacturing processes can contribute even more.

    Food makers are clearly of keeping baby food poison-free: roughly a third of the tested products did not contain worrisome metal levels. Some companies are already trying to look into the sources of contamination in their products and try to reduce them. More companies should follow. But the best chance of real change will come with laws. Currently there are no U. S rules on acceptable levels of heavy metals in baby foods.

    The government and the food industry should unite to deal with the serious threat to our children.

    Walk through the Amazon rainforest today and you will find it steamy, warm, damp and thick. But if you had been there around 15,000 years ago, during the last ice age, would it have been the same? For more than 30 years, scientists have been arguing about how rainforests might have reacted to the cold, dry climate of the ice ages, but till now, no one has reached a satisfying answer.

    Rainforests like the Amazon are important for mopping up CO2 from the atmosphere and helping to solve global warming. Currently the trees in the Amazon take in around 500 million tons of CO2 each year: equal to the total amount of CO2 given off in the UK each year. But how will the Amazon react to the future climate change? If it gets drier, will it survive and continue to draw down CO2? Scientists hope that they will be able to learn in advance how the rainforest will manage in the future by understanding how rainforests reacted to climate change in the past.

    Unfortunately, collecting information is incredibly difficult. To study the past climate, scientists need to look at fossilized pollen (花粉) kept in lake mud. Going back to the last ice age means drilling down into lake sediments (沉淀物), which requires specialized equipment and heavy machinery . There are very few roads and paths, or places to land helicopters and aeroplanes. Rivers tend to be the easiest way to enter the forest, but this still leaves vast areas between the rivers completely unsampled (未取样). So far, only a handful of cores have been drilled that go back to the last ice age and none of them provide enough information to prove how the Amazon forest reacts to climate change.